1. Field of the Invention
The present invention relates to a candle, and more particularly a smokeless candle which generates no or almost no soot during burning thereof and which may contain a perfumery to release a fragrance during burning period of time.
2. Related Arts
Hitherto, bees wax and Japan wax had been used as raw material for preparing illuminating candles, but in the present time, a petroleum wax of paraffin wax and a mixture thereof with polyethylene wax or stearic acid have mainly been used.
Among candles, including Japenese type candles, on the market, there is a so-called xe2x80x9csmokelessxe2x80x9d candle, which shows perfect burning or combustion with no generation of soot under a windless condition. However, when a burning flame of the so-called xe2x80x9csmokelessxe2x80x9d candle on the market flares in the wind or the like, momentary generation of soot, even in a small amount, cannot be avoided.
Japenese Patent 9-188893 (A) discloses a so-called xe2x80x9caroma candlexe2x80x9d for releasing a fragrance during burning. Said xe2x80x9caroma candlexe2x80x9d is composed of a perfume precursor in a wax mixture of paraffin wax, as a main component, as well as polyethylene wax and higher fatty carboxylic acids, as additional components. The xe2x80x9caroma candlexe2x80x9d generates the fragrance by decomposition of the perfume precursor when the candle burns. In recent years, various candles containing perfumery have been marketed for the purpose of aroma therapies because the light or burning flame of these candles has a soothing effect on human psyche.
The candle made of only paraffin wax or a candle containing paraffin wax as a main component burns near a state of perfect combuston with almost no soot generation, if the candle burns in a windless condition, but the candle has the following drawbacks.
(1) When the burning flame flares by the wind or the like, soot momentary generates to make worse environment in room,
(2) The burning flame is somewhat long and thus there is some problem in safety and total burning period of time becomes shorter,
(3) Somewhat strong inherent smell (offensive smell) generates, when the flame of candle is blown out, and
(4) When a liquid perfumery is selected and amount thereof shall be set higher, hardness of the wax becomes low and thus configuration of a candle is limited to a stick type one, if the candle shall be manufactured by a molding process. This means that the wax should be poured into a glass or the like receptacle with various configuration for obtaining a candle with configuration other than stick type one, which candle product must be merchandised together with the receptacle.
A main object of the invention, therefore, is to provide a smokeless candle which contains paraffin wax as one of wax components thereof, wherein the generation of soot is remarkably inhibited or soot is not generated at all.
Another object of the invention is to provide a smokeless candle having a burning flame shorter than that in a conventional candle, so that the total burning period is longer than that of the conventional candle.
Other object of the invention is provide a smokeless candle which can be easily demolded, even if a liquid perfumery is composed into the wax component in somewhat large amount, whereby the candles with various configuration can be manufactured by utilizing a molding process known per se.
A still other object of the invention is to provide a smokeless candle having delicate light color tone with no irregular color tone to give transparent feeling, since some of marketed aroma candles have heavy color tone, although it seems to be that the paraffin wax has low affinity with various coloring matters, more particularly liquid type coloring matters and thus the coloring matter has been used in large amount to avoid generation of irregularity in color tone of the aroma candle.
According to the invention, the main object is attained by a smokeless candle comprising paraffin wax and an insect or Chinese wax, as wax components thereof.
Among the wax components for the smokeless candle according to the invention, the insect wax is that secreted by a secondary larva of Ericerus pela and adhered on a trunk and branches of Fraxinus chinensis and Ligustrum lucidum, which wax shows color tone near pure white by purification thereof and relatively high melting point of 80-83xc2x0 C. The inventors have unexpectedly found the following facts regarding a candle which was prepared by composing the insect wax into paraffin wax to establish the invention.
(a) Generation of soot is remarkably restrained.
(b) Burning flame is short (about 1 cm which is a half of or more less than that of the candle made of paraffin wax) and thus the burning period of time becomes longer (the essential object of the invention lies in providing not an illuminating candle, but an aroma candle, so that the short burning flame is not a drawback but forms an advantage, in view of safety in use.
(c) The offensive smell inherent to the candle made of paraffin wax is not generated, when the flame of candle is blown out.
(d) Even if a liquid perfumery is composed by about 10% by weight to the wax components, the molten wax allows production of candles with good hardness through a molding process, whereby each of the candles generates fragrance with different intensity during burning thereof. The candle normally contains 3-10 g of perfumery per 100 g of wax.
(e) A molten mixture of the waxes shows good affinity with various liquid coloring agents, which allows production of candles having delicate light color tone with no irregularly colored portion to give transparent color feeling.
(f) A tip end of burning flame in a conventional candle points and almost continuously flares by ascending current due to burning of the candle but in case of the candle according to the invention, burning flame shows somewhat roundish tip and is stable as a whole to give a mild or restful feeling.
In the smokeless candle according to the invention, it is preferable that the wax components contain 5-60% by weight of the insect wax. Soot generation is remarkably reduced if the wax components contain about 5% by weight of the insect wax, so that, even if soot is momentarily generated due to flaring or swaying of the burning flame, the amount of soot generated is very slight, since the length of the burning flame is shorter than about 1 cm. In connection with this, please note that the length of the burning flame in commercially available aroma candles is 2 cm or more. If the wax components of the smokeless candle contain about 60% by weight or more of the insect wax, the wax mixture solidified in a mold is too hard, so a crack or breakage may occur at the time of demolding of the candle when the mold has a delicate or complete configuration; and the candle is not preferred based on its production cost.
Depending on the kind of perfumery, some perfumery may give an unpleasant odor, if its concentration in the aroma candle is too high. In the aforesaid Japanese Patent 9-188893(A), there is so described in paragraph No. 0007 that xe2x80x9cas an amount of a perfume precursor in a candle, the precursor is composed so as to occupy to 0.01-20% by weight, more preferably 0.05-10% by weight, and further preferably 0.1-5% by weight, although it depends on the kind of perfumeryxe2x80x9d, namely it is recommended to set the amount of perfumery in relatively low and in the Example, the amount of the precursor is only 1% by weight to wax components called as xe2x80x9cburning materialsxe2x80x9d. In case of the smokeless candle of the present invention, however, there is such a tendency that release of fragrance is suppressed, since the burning flame is shorter, and thus it is necessary to set an amount of the perfumery in somewhat higher level. In case of the conventional aroma candle made of paraffin wax or containing the paraffin wax as main wax component which contains no insect wax, a hardness thereof reduces, when a liquid perfumery is composed in a large amount, to cause the problem during demolding procedure. For manufacturing the candle of the invention, on the contrary thereto, the insect wax having relatively high melting point of 80-83xc2x0 C. is used and, as a result, deformation of the smokeless candle does not occur in demolding. With the smokeless candle of the invention, the amount of melting and flowing wax formed during burning is small, so that there is little crumbling when the candle stops burning in a natural burning out. Namely, in case of the candle according to the invention, a shell portion of the candle remains in a state that substantially retains its original form. Please note that in case of the commercial aroma candle made of paraffin wax, the wax not burned remains in a state having no trace of its original form.
The invention will now be further explained with reference to Test Examples and Manufacturing Examples.
Followings are raw materials used in the Test Examples and Manufacturing Examples.
(1) Waxes
(a) Paraffin Wax:
Commercially available purified product having melting point of 135xc2x0 F.
(b) Insect wax:
Purified product sold by Cera Rica Noda Co., Ltd. of Kanagawa-ken, Japan.
(2) Coloring matters
(a) Red coloring matter:
R-225 (Concentration in use; 0.3 mg/ml).
(b) Blue coloring matter:
B-403 (Concentration in use; 0.3 mg/ml).
(c) Green coloring matter:
G-202 (Concentration in use; 0.3 mg/ml).
(d) Yellow coloring matter:
Y-204 (Concentration in use; 0.1 mg/ml).
Please note that xe2x80x9cR-225xe2x80x9d and so on are symbols for identifying pigments.